The impact of unilateral pulmonary artery stenosis on right ventricular to pulmonary arterial coupling in patients with transposition of the great arteries.

BACKGROUND: Unilateral pulmonary artery (PA) stenosis is common in the transposition of the great arteries (TGA) after arterial switch operation (ASO) but the effects on the right ventricle (RV) remain unclear. AIMS: To assess the effects of unilateral PA stenosis on RV afterload and function in pediatric patients with TGA-ASO. METHODS: In this retrospective study, eight TGA patients with unilateral PA stenosis underwent heart catheterization and cardiac magnetic resonance (CMR) imaging. RV pressures, RV afterload (arterial elastance [Ea]), PA compliance, RV contractility (end-systolic elastance [Ees]), RV-to-PA (RV-PA) coupling (Ees/Ea), and RV diastolic stiffness (end-diastolic elastance [Eed]) were analyzed and compared to normal values from the literature. RESULTS: In all TGA patients (mean age 12 ± 3 years), RV afterload (Ea) and RV pressures were increased whereas PA compliance was reduced. RV contractility (Ees) was decreased resulting in RV-PA uncoupling. RV diastolic stiffness (Eed) was increased. CMR-derived RV volumes, mass, and ejection fraction were preserved. CONCLUSION: Unilateral PA stenosis results in an increased RV afterload in TGA patients after ASO. RV remodeling and function remain within normal limits when analyzed by CMR but RV pressure-volume loop analysis shows impaired RV diastolic stiffness and RV contractility leading to RV-PA uncoupling.

NODAL variants are associated with a continuum of laterality defects from simple D-transposition of the great arteries to heterotaxy.

BACKGROUND: NODAL signaling plays a critical role in embryonic patterning and heart development in vertebrates. Genetic variants resulting in perturbations of the TGF-ß/NODAL signaling pathway have reproducibly been shown to cause laterality defects in humans. To further explore this association and improve genetic diagnosis, the study aims to identify and characterize a broader range of NODAL variants in a large number of individuals with laterality defects. METHODS: We re-analyzed a cohort of 321 proband-only exomes of individuals with clinically diagnosed laterality congenital heart disease (CHD) using family-based, rare variant genomic analyses. To this cohort we added 12 affected subjects with known NODAL variants and CHD from institutional research and clinical cohorts to investigate an allelic series. For those with candidate contributory variants, variant allele confirmation and segregation analysis were studied by Sanger sequencing in available family members. Array comparative genomic hybridization and droplet digital PCR were utilized for copy number variants (CNV) validation and characterization. We performed Human Phenotype Ontology (HPO)-based quantitative phenotypic analyses to dissect allele-specific phenotypic differences. RESULTS: Missense, nonsense, splice site, indels, and/or structural variants of NODAL were identified as potential causes of heterotaxy and other laterality defects in 33 CHD cases. We describe a recurrent complex indel variant for which the nucleic acid secondary structure predictions implicate secondary structure mutagenesis as a possible mechanism for formation. We identified two CNV deletion alleles spanning NODAL in two unrelated CHD cases. Furthermore, 17 CHD individuals were found (16/17 with known Hispanic ancestry) to have the c.778G > A:p.G260R NODAL missense variant which we propose reclassification from variant of uncertain significance (VUS) to likely pathogenic. Quantitative HPO-based analyses of the observed clinical phenotype for all cases with p.G260R variation, including heterozygous, homozygous, and compound heterozygous cases, reveal clustering of individuals with biallelic variation. This finding provides evidence for a genotypic-phenotypic correlation and an allele-specific gene dosage model. CONCLUSION: Our data further support a role for rare deleterious variants in NODAL as a cause for sporadic human laterality defects, expand the repertoire of observed anatomical complexity of potential cardiovascular anomalies, and implicate an allele specific gene dosage model.

Repair of complex transposition of great arteries: What is the best technique to avoid outflow tract obstructions?

OBJECTIVES: This study aimed to evaluate the short-/mid-term outcome of patients with complex dextro (d)-/levo (l)-transposition of the great arteries (TGA), ventricular septal defect and left ventricular outflow tract obstructions. METHODS: A single-centre, retrospective review of all complex dextro-TGA (n = 85) and levo-TGA (n = 22) patients undergoing different surgeries [Arterial switch operation + left ventricular outflow tract obstruction-resection (ASO-R), half-turned truncal switch/Mair (HTTS), Nikaidoh and Rastelli] between May 1990 and September 2022 was performed. Groups were analysed using Kruskal-Wallis test with post hoc pairwise comparison and Kaplan-Meier time-to-event models. RESULTS: A total of 107 patients [ASO-R (n = 20), HTTS (n = 23), Nikaidoh (n = 21), Rastelli (n = 43)] were included, with a median age of 1.0 year (0.5-2.5) and surgical repair median follow-up was 3.8 years (0.3-10.5). Groups did not differ in respect to early postoperative complications/early mortality. Five-year overall survival curves were comparable: ASO-R 78.9% (53.2-91.5), HTTS 75.3% (46.8-89.9), Nikaidoh 85% (60.4-94.9) and Rastelli 83.9% (67.5-92.5), P = 0.9. Highest rates of right ventricular outflow tract (RVOT) reinterventions [33.3% and 32.6% (P = 0.04)] and reoperations [28.6% and 32.6% (P = 0.02)] occurred after Nikaidoh and Rastelli procedures. However, overall freedom from RVOT reinterventions and RVOT reoperations at 5 years did not differ statistically significantly between the groups (ASO-R, HTTS, Nikaidoh and Rastelli): 94.4% (66.6-99.2), 69.1% (25.4-90.5), 67.8% (34-86.9), 64.4% (44.6-78.7), P = 0.2, and 90.0% (65.6-97.4), 91% (50.8-98.7), 65.3% (32.0-85.3) and 67.0% (47.4-80.6), P = 0.3. CONCLUSIONS: Surgical repair of complex dextro-/levo-TGA can be performed with satisfying early/mid-term survival. RVOT reinterventions/reoperations were frequent, with highest rates after Nikaidoh and Rastelli procedures. Left ventricular outflow tract obstruction reoperations were rare with zero events after Nikaidoh and HTTS procedures.

Navigating the spectrum of double-outlet right ventricle presentations: Outcomes from a contemporary cohort based on subtypes.

PURPOSE: Our aim in this study was to investigate the prenatal and postnatal prognosis of double outlet right ventricle (DORV) cases diagnosed prenatally by analyzing the outcomes based on the subtype. METHODS: This study is a retrospective chart review. Cases diagnosed with fetal DORV by prenatal ultrasound in the maternal-fetal medicine department of our hospital between 2014 and 2022 were included. Data on maternal characteristics, fetal echocardiographic features (type of DORV), pregnancy and neonatal outcomes (termination of pregnancy [TOP], intrauterine fetal death [IUD], neonatal death [NND], death in infancy (IND), survival) were collected and analyzed. RESULTS: Ninety-nine cases of prenatally diagnosed cases of DORV were included. The prenatal diagnosis was right in 97% of the liveborn fetuses. The cases were classified into subtypes, including transposition of great arteries (TGA), Fallot, ventricular septal defect (VSD), remote, and heterotaxy types. The cohort consisted of 32.3% TGA type, 19.1% fallot type, 11.1% VSD type, 2% remote type, and 35.3% heterotaxy type of DORV. An additional cardiac anomaly was observed in 87% and an extra-cardiac anomaly was observed in 54% of the cases. When we excluded the cases with heterotaxy type but without any chromosomal abnormality, additional genetic abnormalities were detected in 42% of the remaining cases. Outcome of pregnancy was livebirth in 68/99 (68.7%), IUFD in 5/99 (5.1%), and TOP in 26/99 (26.3%). Postnatal cardiac surgical repair was performed in 48 cases. Survival among livebirths was 39/68 (57.3%). Twenty-nine neonates or infants who had additional cardiac anomalies and/or genetic abnormalities died before any surgical intervention. The postoperative survival rate was 39/48 (81.2%). CONCLUSION: The prognosis in DORV depends on the anatomical subtype, the presence, and severity of associated anomalies. Survival increases in isolated cases without any additional structural or genetic anomalies.

Predicting High-Risk Fetal Cardiac Disease Anticipated to Need Immediate Postnatal Stabilization and Intervention with Planned Pediatric Cardiac Operating Room Delivery.

BACKGROUND: Distances between delivery and cardiac services can make the care of fetuses with cardiac disease at risk of acute cardiorespiratory instability at birth a challenge. In 2013 we implemented a fetal echocardiography-based algorithm targeting fetuses considered high risk for acute cardiorespiratory instability at ≤2 hours of birth for delivery in our pediatric cardiac operating room of our children's hospital, and, herein, examine our experience. METHODS AND RESULTS: We reviewed maternal and postnatal medical records of all fetuses with cardiac disease encountered January 2013 to March 2022 considered high risk for acute cardiorespiratory instability. Secondary analysis was performed including all fetuses with diagnoses of d-transposition of the great arteries/intact ventricular septum (d-TGA/IVS) and hypoplastic left heart syndrome (HLHS) encountered over the study period. Forty fetuses were considered high risk for acute cardiorespiratory instability: 15 with d-TGA/IVS and 7 with HLHS with restrictive atrial septum, 4 with absent pulmonary valve syndrome, 3 with obstructed anomalous pulmonary veins, 2 with severe Ebstein anomaly, 2 with thoracic/intracardiac tumors, and 7 others. Pediatric cardiac operating room delivery occurred for 33 but not for 7 (5 with d-TGA/IVS, 2 with HLHS with restrictive atrial septum). For high-risk cases, fetal echocardiography had a positive predictive value of 50% for intervention/extracorporeal membrane oxygenation/death at ≤2 hours and 70% at ≤24 hours. Of "low-risk" cases, 6/46 with d-TGA/IVS and 0/45 with HLHS required intervention at ≤2 hours. Fetal echocardiography for predicting intervention/extracorporeal membrane oxygenation/death at ≤2 hours had a sensitivity of 67%, specificity 93%, and positive and negative predictive values of 80% and 87%, respectively, for d-TGA/IVS, and 100%, 95%, 71%, and 100% for HLHS, respectively. CONCLUSIONS: Fetal echocardiography can predict the need for urgent intervention in a majority with d-TGA/IVS and HLHS and in half of the entire spectrum of high-risk cardiac disease.

En Bloc Rotation of the Outflow Tracts - Double Root Translocation.

En bloc rotation of the outflow tracts or double root translocation offers an anatomic repair of transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction and closely related forms of double outlet right ventricle. The technical principle is to excise aortic and pulmonary root en bloc, rotate them as a whole by 180°, and reimplant them. The left ventricular outflow tract is enlarged with the patch closing the ventricular septal defect. In our experience, two thirds of the pulmonary valves could be preserved. Growth of the aortic and pulmonary root could be demonstrated in several studies performed by our group. It is still a complex and technically demanding procedure with long cardiopulmonary bypass periods and cross-clamp times. However, perioperative mortality and complications do not differ significantly from other forms of reconstruction. The reoperation rate is significantly lower. Presently, the best time to perform this operation seems to be after the newborn period within the first year of life.

Perfusion techniques for an 800 g premature neonate undergoing Arterial Switch Procedure for Transposition of the Great Arteries☠.

Early cardiac surgery in neonates and infants with congenital heart disease has been performed since the middle to late years of the twentieth century. To date, there are very few reports of successful congenital heart surgery using cardiopulmonary bypass (CPB) in premature babies less than 1000 g with serious congenital heart disease. Limited information is available in the literature describing perfusion techniques for this extremely fragile patient population. Miniaturization of the CPB circuit contributes to multiple factors that affect this population significantly. These factors include the reduction of patient-to-circuit ratios, volume of distribution of pharmacological agents, management of pressure gradients within the CPB system, and increased tactile control by the attending perfusionist. Careful management of the physiological environment of the patient is of utmost importance and can mitigate risks during CPB, including volume shifts into the interstitial space, electrolyte, and acid-base imbalance, and intracranial hemorrhage. We report perfusion techniques successfully utilized during the surgical repair of transposition of the great arteries for an 800 g, 28-week-old neonate. CPB techniques for the smallest and youngest patients may be executed safely when proper physical, chemical, and perfusion process adjustments are made and managed meticulously.

Antifungal medication use during early pregnancy and the risk of congenital heart defects in the National Birth Defects Prevention Study, 1997-2011.

BACKGROUND: Fungal infections are common among pregnant people. Recent studies suggest positive associations between oral antifungals used to treat fungal infections and congenital heart defects (CHDs). METHODS: We estimated associations between first trimester antifungal use and 20 major, specific CHDs using data from the National Birth Defects Prevention Study (NBDPS), a multi-site, case-control study that included pregnancies with estimated delivery dates from October 1997 through December 2011. Infants with CHDs ("cases") were ascertained from 10 birth defect surveillance programs. Live born infants without major birth defects ("controls") were randomly selected from birth records or hospital discharge lists. First trimester antifungal use was self-reported via maternal interview. We estimated adjusted odds ratios (AORs) and 95% confidence intervals (CIs) using logistic regression with Firth's penalized likelihood. RESULTS: First trimester antifungal use was reported by 148/11,653 (1.3%) case and 123/11,427 (1.1%) control participants. We estimated AORs for 12 CHDs; six had AORs >1.5 (tetralogy of Fallot, double outlet right ventricle with transposition of the great arteries [DORV-TGA], atrioventricular septal defect, hypoplastic left heart syndrome, pulmonary atresia, muscular ventricular septal defect), and one (pulmonary valve stenosis) had an AOR <0.7. All CIs included the null, except for DORV-TGA. CONCLUSIONS: First trimester antifungal use was rare. We observed some positive associations for several specific CHDs in our analysis, although the CIs largely included the null. Results do not support a large increase in risk, but smaller increases in risk for certain CHD cannot be ruled out.

Use of Interactive Visualization and 3D Printing in the Repair of Complex Congenital Heart Disease Presenting in Adult Life.

We report a case of a 25-year-old male with a heterotaxy-like constellation of congenital heart defects consisting of complete atrioventricular septal defect, transposition of the great arteries, subpulmonary stenosis, L-looped ventricles, hypoplastic right ventricle, and a distant aorta arising from the right ventricle. This case demonstrates how 3D printing and interactive 3D visualization may facilitate a unique surgical repair.

Perioperative Factors and Radiographic Severity Scores for Predicting the Duration of Mechanical Ventilation After Arterial Switch Surgery.

OBJECTIVES: Cardiac surgery on cardiopulmonary bypass (CPB) during the neonatal period can cause perioperative organ injuries. The primary aim of this study was to determine the incidence and risk factors associated with postoperative mechanical ventilation duration and acute lung injury after the arterial switch operation (ASO). The secondary aim was to examine the utility of the Brixia score for characterizing postoperative acute lung injury (ALI). DESIGN: A retrospective study. SETTING: A single-center university hospital. PARTICIPANTS: A total of 93 neonates with transposition of great arteries with intact ventricular septum (dTGA IVS) underwent ASO. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: From January 2015 to December 2022, 93 neonates with dTGA IVS were included in the study. The cohort had a median age of 4.0 (3.0-5.0) days and a mean weight of 3.3 ± 0.5 kg. About 63% of patients had ≥48 hours of postoperative mechanical ventilation after ASO. Risk factors included prematurity, post-CPB transfusion of salvaged red cells, platelets and cryoprecipitate, and postoperative fluid balance by univariate analysis. The larger transfused platelet volume was associated with the risk of ALI by multivariate analysis. The median baseline Brixia scores were 11.0 (9.0-12.0) and increased significantly in the postoperative day 1 in patients who developed moderate ALI 24 hours after admission to the intensive care unit (15.0 [13.0-16.0] v 12.0 [10.0-14.0], p = 0.046). CONCLUSIONS: Arterial switch operation results in a high incidence of ≥48-hour postoperative mechanical ventilation. Blood component transfusion is a potentially modifiable risk factor. The Brixia scores also may be used to characterize postoperative acute lung injury.

Safety and efficacy of combined dilation/stenting of venous abnormalities, including complete obstructions, during lead extractions in patients with congenital heart disease.

INTRODUCTION: Management of transvenous leads in patients with congenital heart disease (CHD) can be complicated by venous obstructions and residual shunts. We present our experience performing concurrent lead extraction and dilation/stenting of venous pathways, including patients with complete venous obstruction. METHODS: All cases of concurrent lead extraction and recanalization of vena cavae/baffles between 2017 and 2021 at Boston Children's Hospital were retrospectively included and reviewed for safety and efficacy. RESULTS: Eight patients, 4 female, median 38.5 years of age (range 16.7-49 years) and 81.6 kg weight (range 41.3-97.8 kg) at time of procedure were included. All patients had CHD, a majority (n = 7) having transposition of the great arteries palliated via atrial switch. All leads were removed in their entirety, with most patients having two leads extracted (n = 7). Median lead dwell time was 13.8 years (range 3.6-35.3 years). Three patients had complete obstructions, three required stenting of their innominate veins and three required recanalization of their femoral vessels. Median procedure time was 9.8 h (range 5.4-12.8 h). Complications included blood transfusion (n = 2), arrhythmia (n = 3), pleural effusion (n = 1), and pressure ulcer (n = 1). There were no cardiac perforations, venous tears, or deaths. CONCLUSION: Lead extraction along with dilation and stenting of venous anomalies, though long in duration, proved effective with minimal complications. This combined procedure can safely and effectively resolve complete obstructions secondary to transvenous leads.

Critical congenital heart disease: contemporary prenatal screening performance and outcomes in a multi-centre perinatology service.

BACKGROUND: Prenatal detection of critical congenital heart disease (CCHD) optimises perinatal decision-making and neonatal outcomes. The objective of this study was to determine the prenatal screening performance, care pathways and perinatal outcomes for prenatally and postnatally diagnosed cases of CCHD over a four-year period. STUDY DESIGN: This retrospective cohort study in a tertiary centre and its two affiliated secondary sites examined all cases of CCHD, including cases of pregnancy termination and in-utero fetal death, neonatal death and liveborn babies that underwent cardiac catheterization or surgery in the first six weeks of life. Prenatal and postnatal data were ascertained from the first trimester assessment for all patients diagnosed prenatally. Cases requiring intervention that were first identified in the postnatal period were included to determine prenatal detection rates. Follow-up for all cases of CCHD continued to one year of age. RESULTS: In a consecutive cohort of 49,950 pregnancies in a 4-year period 01/2019 to 12/2022, a prenatal diagnosis of CCHD was made in 96 cases, yielding a prevalence of 1.9 per 1000 births. The prenatal detection for right duct-dependant heart pathology and congenital heart block was 100%, 85% for left duct-dependant pathology and 93% for transposition of the great arteries (TGA). In the prenatally diagnosed group, 37% of cases were complicated by extracardiac structural abnormalities, a genetic diagnosis or both. All cases of prenatal detection were identified in the context of routine anatomy screening rather than specialist Fetal Cardiac screening services. Almost half of all pregnancies complicated by CCHD did not undergo neonatal cardiac intervention, by virtue of parental choice determined either prenatally or after birth. An additional eight babies were diagnosed with CCHD in the neonatal period, such that the prenatal detection rate for CCHD was 92% (96/104, 95% CI = 84%-96%). Survival at 1-year for infants deemed suitable for CCHD surgery was 85%. CONCLUSION: In a large unselected population, optimal rates of prenatal detection of critical congenital heart disease can be achieved by a protocolised approach to mid-trimester fetal anatomy ultrasound, underpinned by a programme of sonographer education and training. The cardiac abnormalities most likely to evade prenatal detection are left-sided obstructive lesions.

Outcomes of delayed chest closure after congenital heart surgery in neonates.

We present the outcomes of delayed chest closure in neonates who underwent congenital heart surgery under cardiopulmonary bypass. Eighty-one consecutive neonatal patients (age ≤ 28 days) with congenital heart diseases who underwent heart operations and after surgery, chest remained open in the intensive care unit until DCC. Correction of transposition of the great arteries pathology was the most common surgical procedure (48.1% of patients). Median sternal closure time from surgery was 3 (2-4) days. Median age of neonates was 9 (5-12) days. In addition, in 4 cases (4.9%) there was secretion from the surgical site after DCC and after taking cultures, in 2 (2.4%) of the cases a pathogen was identified. Multivariable linear regression analysis (adjusted to gender and CPB) showed that only the age-predicted the sternum closure time (ß=-0.09, 95%CI: - 0.16 to -0.02, p=0.02). In-hospital mortality was 6 (7.4%) patients. Although the DCC in neonates who underwent CHD surgical correction was related to a high mortality rate, only the age of neonates predicted the sternum closure time in the ICU.

Bioptome-assisted blunt dissection facilitates endovascular retrieval of a chronically embolized stent.

We present a 19-year-old female with history of d-transposition of the great arteries status post-arterial switch operation.

Percutaneous pulmonary valve implantation in a patient with congenitally corrected transposition of the great arteries: a case report.

BACKGROUND: Percutaneous pulmonary valve implantation has become an attractive method of dysfunctional right ventricle outflow tract treatment. CASE PRESENTATION: We describe a unique case of a 20-year-old Caucasian male patient with a complex cyanotic heart defect, namely pulmonary atresia, with congenitally corrected transposition of the great arteries and ventricular septal defect after Rastelli-like surgery at the age of 5 years with homograft use. At the age of 20 years, the patient needed percutaneous pulmonary valve implantation owing to homograft dysfunction. Despite unusual course of the coronary arteries, balloon testing in the landing zone of the right ventricle outflow tract excluded potential coronary artery compression. Then, after presentation, a Melody valve was implanted successfully in the pulmonary valve position. The 8-year follow-up was uneventful. CONCLUSION: This is likely the first description of a percutaneous pulmonary valve implantation in such anatomy. Such a procedure is feasible; however, it requires exceptional caution owing to the anomalous coronary arteries course, which can be the reason for their compression.

National population-based estimates for major birth defects, 2016-2020.

BACKGROUND: We provide updated crude and adjusted prevalence estimates of major birth defects in the United States for the period 2016-2020. METHODS: Data were collected from 13 US population-based surveillance programs that used active or a combination of active and passive case ascertainment methods to collect all birth outcomes. These data were used to calculate pooled prevalence estimates and national prevalence estimates adjusted for maternal race/ethnicity for all conditions, and maternal age for trisomies and gastroschisis. Prevalence was compared to previously published national estimates from 1999 to 2014. RESULTS: Adjusted national prevalence estimates per 10,000 live births ranged from 0.63 for common truncus to 18.65 for clubfoot. Temporal changes were observed for several birth defects, including increases in the prevalence of atrioventricular septal defect, tetralogy of Fallot, omphalocele, trisomy 18, and trisomy 21 (Down syndrome) and decreases in the prevalence of anencephaly, common truncus, transposition of the great arteries, and cleft lip with and without cleft palate. CONCLUSION: This study provides updated national estimates of selected major birth defects in the United States. These data can be used for continued temporal monitoring of birth defects prevalence. Increases and decreases in prevalence since 1999 observed in this study warrant further investigation.